Paint coating system

ABSTRACT

A cartridge changer ( 41 ) is composed of a swing arm ( 48 ) with a cartridge gripper ( 48 B) for gripping a paint cartridge ( 24 ), and an arcuate moving portion ( 46 ) for putting the swing arm ( 48 ) in swinging movements in a horizontal plane. The cartridge changer ( 41 ) is adapted to pick up a replenished paint cartridge ( 24 ) on the mount deck ( 42 ) by the cartridge gripper ( 48 B) and transfer the swing arm ( 48 ) to a changing position “O” by the arcuate moving portion ( 46 ). By the operation, a used paint cartridge ( 24 ′) will be replaced by the replenished paint cartridge ( 24 ) between the mount deck ( 42 ) and a common body ( 15 ) which is located in the changing position “O” of the atomizing head changing and washing device ( 31 ).

TECHNICAL FIELD

This invention relates to a paint coating system particularly suitablefor use, for example, in coating vehicle bodies, furniture, electricappliances and the like.

BACKGROUND ART

Generally, paint coating systems in use for painting vehicle bodies andthe like are largely constituted by a robot device with an articulatedarm, and a coater unit mounted on a distal end of the robot arm of therobot device and provided with an atomizing head for spraying atomizedpaint particles.

Among paint coating systems of this sort, there is a system providing apaint cartridge replenished by a paint which will be supplied to anatomizing head of the coater unit and can be replaceably attached to acommon body which is mounted on a distal end of a robot arm of the robotdevice (see, for example, Patent Literature 1: Japanese Patent Laid-OpenNo. 2000-176333).

More particularly, the paint coating system described in theabove-mentioned Patent Literature 1 employs a cartridge changerproviding a plural number of paint cartridges of each different colorson a mount deck. This cartridge changer is largely constituted by amount deck on which a plural number of paint cartridges are set, a paintreplenisher provided on the mount deck and replenishing consumed paintcartridges, and a cartridge transfer mechanism adapted to transfer agripped paint cartridge in longitudinal and transverse directions of themount deck in addition to upward and downward directions.

The cartridge transfer mechanism is composed of a first transfermechanism having a carriage which is movable on and along a pair ofrails extending longitudinally of the mount deck, a second transfermechanism provided on the carriage of the first transfer mechanismhaving a carriage which is movable on and along a pair of transverselyextending rails, and a third transfer mechanism provided on the carriageof the second transfer mechanism to move a cartridge gripper in upwardand downward directions.

At the time of replacing a paint cartridge on a common body of a coaterunit, the coater unit is placed at a predetermined cartridge changingposition by an action of a robot arm of a robot device, and the robotarm is stopped at that position. In this state, a used paint cartridgeat the changing position is picked up and moved upward by means of thecartridge transfer mechanism of the cartridge changer, disconnecting andseparating the used paint cartridge from the common body. In the nextplace, while the common body is fixedly retained in the predeterminedchanging position by the robot device, a replenished paint cartridgefull of paint is transferred to the changing position and set on thecommon body from above by the cartridge transfer mechanism.

On the other hand, there is a paint coating system providing a pluralnumber of atomizing heads to be replaceably and interchangeably mountedon a common body of a coater unit by means of an atomizing head changer(see, for example, Patent Literature 2: Japanese Patent Laid-Open No.2001-79463).

In the case of the paint coating system described in the above-mentionedPatent Literature 2, when replacing an atomizing head on a common bodyof a coater unit, a robot arm of the robot device operates to attach anatomizing head which is mounted on the common body to an atomizing headgripper of an atomizing head changing and washing device. In this state,the common body is lifted up by the robot device to detach the usedatomizing head from the common body. On the other hand, after detachmentof the used atomizing head, the common body is transferred by a robotdevice to a head changing position for replacement by another atomizinghead which is gripped on the atomizing head gripper.

Further, there is another paint coating system which is composed of arobot device for coating, a coater unit which is mounted on a robot armof the robot device for spraying atomizing paint, a number of paintcartridges filled with paint of different colors to be replaceably andinterchangeably mounted on the robot arm of the robot device, and acartridge changer adapted to mount a paint cartridge of a respectivecolor replaceably on the robot arm of the robot device (see, forexample, Patent Literature 3: International Publication WO 97/34707).

The cartridge changer described in above-mentioned Patent Literature 3is composed of a rotary table on which a plural number of cartridges areplaced in an arcuate formation, and a cartridge gripper which loads acartridge provided on the rotary table into an opening socket of a robotarm of a robot device.

By the way, in the case of Patent Literature 1 mentioned above, thecartridge transfer mechanism is arranged as an XY table to transfer apaint cartridge in the directions of two orthogonal axes by means of thefirst transfer mechanism extending in the longitudinal direction and thesecond transfer mechanism extending in the transverse direction of thefirst transfer mechanism. This XY table is constructed by mounting heavyrails and carriage of the second transfer mechanism on the firsttransfer mechanism. Due to heavy weight, the two transfer mechanisms aredifficult to start and stop a transfer action speedily. That is to say,the cartridge transfer mechanisms of this type are necessarily requiredto lower the transfer speed in order to transfer a paint cartridgeaccurately to a specific position, resulting in a longer changingoperation time and a considerable degradation in productivity.

On the other hand, in the case of the paint coating system described inPatent Literature 2 mentioned above, an atomizing head is replaced bymoving a coater unit in downward and upward directions relative to anatomizing head gripper which is held in a fixed state. On the otherhand, in the case of the paint coating system of Patent Literature 2, arobot arm of a robot device is stopped at a predetermined cartridgechanging position to locate and set a coater unit in that position whilea paint cartridge is replaced by a cartridge changer.

However, in the case of a robot device which is in use for paint coatingoperations, with regard to the repeated positioning accuracy in motioncontrol such as moving, stopping, posture and the like of a coater unitwhich is mounted on a distal end of a robot arm, there is inevitably anerror of several millimeters. Therefore, even if the coater unit ismoved to a predetermined position for changing an atomizing head or apaint cartridge in response to the same control command after finishinga certain coating operation by the robot device, actually it is oftenthe case that the coater unit is located in a position which is somewhatdeviated from the predetermined changing position. Therefore, if thechanging operation is carried out depending upon the accuracy of motioncontrol on the part of the robot device alone, this deviation from thepredetermined changing position may result in exertion of a forcibleload between a common body and the atomizing head or the paintcartridge, shortening the service life of the coater unit by repeatedabrasive and damaging contact.

Besides, a robot device is required to be operative with an extremelyhigh degree of accuracy in locating a coater unit in a predeterminedspecific position at the time of changing a paint cartridge, and, inorder to meet this requirement, needs to be installed with highdimensional accuracy despite a considerable increase in cost.

Further, in the case of the paint coating system according to PatentLiterature 3, a coater unit which is attached on a robot arm is notequipped with a replaceable paint atomizing head. Therefore, in thiscase, there is a problem of low productivity because it is impossible tocarry out a paint washing operation and a coating operationsimultaneously.

In addition, washer is not provided for washing a head portion of acoater unit. This means that it is necessary to wash a robot arm and acoater unit every time when replacing a paint cartridge on the robot armby a cartridge of a different color.

Furthermore, the paint coating system according to Patent Literature 3,a rotary table on which paint cartridges are placed is rotated by amotor while a cartridge gripper is arranged to move linearly, requiringa large space for installation and a mechanism of complicateconstruction.

DISCLOSURE OF THE INVENTION

In view of the above-discussed problems with the prior art, it is anobject of the present invention to provide a paint coating systemadopting a cartridge changer which is reduced in weight and operativesmoothly and efficiently in replacing paint cartridges by the cartridgechanger.

(1) A paint coating system according to the present invention, iscomposed of: a robot device operative to take coating actions; a coaterunit having a common body fixedly mounted on the robot device and anatomizing head replaceably attached to the common body for sprayingatomized paint particles; a paint cartridge replaceably attached to thecommon body of the coater unit to supply paint to the atomizing head; anatomizing head changing and washing device adapted to replace a usedatomizing head on the common body of the coater unit by a washed cleanatomizing head and to wash the dismantled used atomizing head clean; anda cartridge changer adapted to pick up a selected paint cartridge amonga plural number of replenished paint cartridges arrayed on a mount deck,and to replace a used paint cartridge on the common body of the coaterunit in changing position of the atomizing head changing and washingdevice by the selected paint cartridge.

In order to achieve the above-stated objectives, the cartridge changeris provided with a swing arm adapted to replace the paint cartridgewhile being swung to and fro about a swing arm pivoting point along anarcuate path between a position of the replenished paint cartridge onthe mount deck and a changing position of the atomizing head changingand washing device.

With the arrangements just described, the swing arm of the cartridgechanger is put in a swinging movement along an arcuate path about aswing arm pivoting point at the time of replacing a used paint cartridgeon a coater unit at a changing position of an atomizing head changingand washing device by a replenished paint cartridge on a mount deck. Inthis case, although very simple in construction, the swing arm cantransfer a plural number of replenished paint cartridges provided on themount deck by its swinging movements along arcuate paths.

As a consequence, the cartridge changer can be significantly reduced inweight of the swing arm to lessen loads which are imposed on variousmoving parts, guaranteeing higher working speed and improved brakingability. That is to say, the cartridge changer can complete a cartridgereplacing operation in a shorter time period without degradations incontrol accuracy, achieving improvements in productivity.

(2) According to the present invention, replenished paint cartridges onthe mount deck are arranged in arcuate rows around the swing armpivoting point.

In this case, a plural number of replenished paint cartridges arearranged in arcuate rows on the mount deck along an arcuate path oftransfer of the cartridge changer, so that a paint cartridge can bereplaced by the swing arm while swung along the arcuate path totransfer.

(3) According to the present invention, preferably the cartridge changeris composed of the mount deck adapted to mount the replenished paintcartridges located in arcuate rows about the swing arm pivoting point,an arcuate moving portion provided on the mount deck and circulated toand fro about the pivoting point, a vertical moving portion provided onthe arcuate moving portion for vertical upward and downward movements,and the swing arm which extends in a horizontal plane attached to thevertical moving portion at a base end and provided with cartridgegrippers at and on a fore free end thereof.

In this case, a replenished paint cartridge is gripped in a cartridgegripper which is provided at a fore distal end of the swing arm of thecartridge changer, and then the cartridge gripper is lifted up by thevertical moving portion together with the replenished paint cartridge.The cartridge gripper is then moved along arcuate row on the swing armpivoting point by the arcuate moving portion. Thus, the cartridgechanger is capable of dismantling a used paint cartridge from the commonbody of the coater unit which is fixedly retained at the changingposition of the atomizing head changing and washing device, or mountinga replenished paint cartridge.

(4) According to the present invention, preferably the cartridge changeris composed of the mount deck adapted to mount said replenished paintcartridges located in a plural number of radially spaced arcuate rowsaround the swing arm pivoting point, a linear moving portion forshifting the swing arm pivoting point provided on the mount deck in alongitudinal direction, an arcuate moving portion provided on the linearmoving portion circulated to and fro about the pivoting point, avertical moving portion provided on the arcuate moving portion forvertical upward and downward movements, and the swing arm which extendsin a horizontal plane attached to the vertical moving portion at a baseend and provided with cartridge grippers at and on a fore free endthereof.

In this case, a replenished paint cartridge is gripped in a cartridgegripper, which is provided at a fore distal end of the swing arm of thecartridge changer, and then the cartridge gripper is lifted up by thevertical moving portion together with the replenished paint cartridge.The cartridge gripper is then moved along arcuate row on the swing armpivoting point by the arcuate moving portion, and the position of thecartridge gripper is shifted by the linear moving portion in alongitudinal direction of the mount deck.

Thus, the cartridge changer is capable of dismantling a used paintcartridge from the common body of the coater unit which is fixedlyretained at the changing position of the atomizing head changing andwashing device or mounting a replenished paint cartridge. In this case,a greater number of paint cartridges can be set on the mount deck simplyby increasing the number of the arcuate cartridge rows on the mountdeck.

(5) According to the present invention, preferably the atomizing headchanging and washing device is provided with a common body gripper togrip and locate the common body of the coater unit at the changingposition “O”, and the cartridge changer is adapted to replace the paintcartridge while the common body is gripped by the common body gripper.

In this case, at the time of replacing an atomizing head and a paintcartridge on a common body of a coater unit, the robot device moves thecoater unit to the changing position of the atomizing head changing andwashing device, and the common body of the coater unit is gripped on acommon body gripper which is provided at that changing position. Sothat, a positional deviation which may have occur due to an error inrepeated positioning accuracy of the robot device or due to aninstallation error of the robot device may be absorbed. Thus, it ispossible to position the common body of the coater unit exactly at thechanging position of the atomizing head changing and washing device.

As a consequence, an atomizing head and a paint cartridge can bedismantled from or mounted on the common body very smoothly to guaranteean elongated service life for these components. Besides, theinstallation work for the robot device, the installation and possessingwork for the atomizing head changing and washing device or the cartridgechanger can be carried out efficiently in a facilitated manner. Inaddition, the cost of a coating line as a whole can be cut down to asignificant degree

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a perspective view of a vehicle body coating lineincorporating a paint coating system embodying the present invention;

FIG. 2 is a plan view of the vehicle body coating line of FIG. 1;

FIG. 3 is an enlarged perspective view of a coater unit which is mountedon a wrist of a robot device;

FIG. 4 is a longitudinal sectional view of the coater unit, taken fromthe direction of arrows IV-IV of FIG. 3;

FIG. 5 is a longitudinal sectional view, showing a common body portionof the coater unit of FIG. 4;

FIG. 6 is a longitudinal sectional view of an atomizing head shown inFIG. 4;

FIG. 7 is a longitudinal sectional view of a paint cartridge shown inFIG. 4;

FIG. 8 is a front view of an atomizing head changing and washing deviceand a paint cartridge changer;

FIG. 9 is a right-hand side view of the atomizing head changing andwashing device and the paint cartridge changer, taken from the directionof arrows IX-IX of FIG. 8;

FIG. 10 is a partly cutaway plan view showing on an enlarged scale theatomizing head changing and washing device and the paint cartridgechanger of FIG. 8;

FIG. 11 is a front view showing on an enlarged scale the atomizing headchanging and washing device of FIG. 8;

FIG. 12 is a right-hand side view of the atomizing head changing andwashing device shown in FIG. 11;

FIG. 13 is a plan view of the atomizing head changing and washing deviceshown in FIG. 11;

FIG. 14 is a sectional view of the atomizing head changing and washingdevice, taken from the direction of arrows XIV-XIV of FIG. 11;

FIG. 15 is a front view of a fixed plate and an elevator;

FIG. 16 is a right-hand side view of the fixed plate and elevator shownin FIG. 15;

FIG. 17 is a schematic illustration explanatory of an operational actionof positioning a common body of a coater unit between pawls of a commonbody gripper;

FIG. 18 is a schematic illustration explanatory in an enlarged view ofan operational action of positioning the common body of the coater unitbetween pawls of the common body gripper, taken from the direction ofarrows XVIII-XVIII of FIG. 17;

FIG. 19 is a schematic illustration explanatory of an operational actionof gripping the common body of the coater unit by pawls of the commonbody gripper;

FIG. 20 is a schematic illustration explanatory in an enlarged view ofan operational action of gripping the common body of the coater unitbetween pawls of the common body gripper, taken from the direction ofarrows XX-XX of FIG. 19;

FIG. 21 is a plan view showing on an enlarged scale a gripping member ofan atomizing head gripper;

FIG. 22 is a partly cutaway enlarged front view of an atomizing headwhich is gripped by a gripping member of the atomizing head gripper;

FIG. 23 is a front view of a washer which is located on the left side inFIG. 11;

FIG. 24 is a right-hand side view of the washer, taken from thedirection of arrows XXIV-XXIV of FIG. 23;

FIG. 25 is a sectional view of a cartridge changer, taken from thedirection of arrows XXV-XXV of FIG. 10;

FIG. 26 is an enlarged sectional view of the cartridge changer, takenfrom the direction of arrows XXVI-XXVI of FIG. 25;

FIG. 27 is an enlarged sectional view of a cartridge transfer mechanism,taken from the direction of arrows XXVII-XXVII of FIG. 26;

FIG. 28 is an enlarged sectional view of an arcuate moving portion, avertical moving portion and a swing arm, taken from the direction ofarrows XXVIII-XXVIII of FIG. 27;

FIG. 29 is a right-hand side view of cartridge grippers on the swingarm, taken from the direction of arrows XXIX-XXIX of FIG. 28;

FIG. 30 is a schematic illustration explanatory of an operational actionof transferring a coater unit to a common body gripper;

FIG. 31 is a schematic illustration explanatory of an operational actionof transferring a replenished paint cartridge toward the atomizing headchanging and washing device;

FIG. 32 is a schematic illustration explanatory of an operational actionof positioning a cartridge gripper on the swing arm above a replenishedpaint cartridge to be used in a next coating operation in a plane view;

FIG. 33 is a schematic illustration explanatory of an operational actionof moving a replenished paint cartridge toward a changing position sideby swing arm in a plane view;

FIG. 34 is a schematic illustration explanatory of operational action ofdetaching a used atomizing head from a common body, while holding a usedpaint cartridge in a gripped state;

FIG. 35 is a schematic illustration explanatory of an operational actionof moving an atomizing head gripper to the left and detaching a usedpaint cartridge;

FIG. 36 is a schematic illustration explanatory of an operationalactions of mounting a washed atomizing head on a common body, andplacing a replenished paint cartridge in a changing position;

FIG. 37 is a schematic illustration explanatory of an operational actionof mounting a replenished paint cartridge on a common body;

FIG. 38 is a schematic illustration explanatory of an operationalaction, showing the swing arm which has been moved to an upper position;

FIG. 39 is a schematic illustration explanatory of operational actionsof moving a coater unit to a standby position for coating operation, andmoving a used paint cartridge to a cartridge changer;

FIG. 40 is a schematic illustration explanatory of operational actionsof detaching a used paint cartridge from a common body and attaching areplenished paint cartridge to the common body as a replacement in aplane view;

FIG. 41 is a schematic illustration explanatory of an operational actionof returning a used paint cartridge to a paint replenishing unit afterdetachment from the common body in a plane view;

FIG. 42 is a schematic illustration explanatory of an operational actionof washing a used atomizing head by a washer;

FIG. 43 is a schematic illustration explanatory of an operational actionof holding a washed atomizing head in a standby state for a replacingoperation; and

FIG. 44 is a flow chart showing operational steps for replacement of anatomizing head and a paint cartridge.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereafter, with reference to FIGS. 1 through 44, the paint coatingsystem of the present invention is described more particularly by way ofits preferred embodiment which is applied as a vehicle body paintingsystem, for example.

In FIGS. 1 and 2, indicated at 1 is a coating line for coating a vehiclebody 2. Moreover, at the half way of the conveyer 3, paint coatingsystem 11, which will be described hereinafter, are located on theopposite side of the conveyer 3.

Indicated at 11 are paint coating systems which are located at the halfway and cooperatively on the opposite sides of the conveyer 3. Each oneof the paint coating systems 11 is largely constituted by a robot device13, a coater unit 14, an atomizing head changing and washing device 31,and a cartridge changer 41, which will be described hereinafter.

Designated at 12 are tracking rails which are located in predeterminedtransversely spaced positions on the opposite side of the conveyer 3 inparallel relation with the latter. Each one of these tracking rails 12constitutes a tracking mechanism to let each robot device 13, which willbe described hereinafter, follow movements of a vehicle body 2 which istransferred by the conveyer 3.

Indicated at 13 are robot devices which are mounted on the trackingrails 12 for coating actions. The robot devices 13 are operative forpainting the vehicle body 2 complying with the teaching instructionwhile letting coater units 14 provided on the distal ends of the robotdevice 13, which will be described hereinafter, follow the vehicle body2.

Further, the robot devices 13 are mounted on the tracking rails 12 andmoved substantially in parallel relation with the conveyer 3, while eachone of coater units 14 is put in coating actions along the vehicle body2 to paint the latter from front to rear side. Moreover, the robotdevices 13 are able to move a coater unit 14 as far as an atomizing headchanging and washing device 31 to locate the coater unit 14 in apredetermined changing position “O” for replacement.

Each robot device 13 which is mounted on the tracking rails 12 isprovided with a multiarticular arm, and constructed of a carriage 13Awhich is movable in the transfer direction of the conveyer 3, a verticalarm 13B which is rotatably and swingably mounted on the carriage 13A, ahorizontal arm 13C which is swingably connected to a fore distal end ofthe vertical arm 13B, and a wrist 13D which is rotatably and pivotallyprovided at a fore distal end of the horizontal arm 13C.

In this instance, when a common body 15 of a coater unit 14 is grippedby a common body gripper 33, which will be described hereinafter, robotdevices 13 are controlled in a reduced power mode, lowering levels ofdriving forces (driving torques) which are generated in rotating motors,reciprocating actuators and the like (none of which is shown in thedrawings) to put the arms 13B and 13C and the wrist 13D in predeterminedmotions. In this reduced power mode, the arms 13B and 13C as well as thewrist 13D and the like of the robot device 13 is freely movable statewhen an external force is applied. Thus, the common body 15 of thecoater unit 14 becomes freely movable in any direction, permitting thecommon body gripper 33 to move the coater unit 14 in an arbitrarydirection to set the common body 15 accurately in a predeterminedchanging position “O”.

Indicated at 14 is a coater unit which is mounted on the wrist 13D atthe fore distal end of the horizontal arm 13C which constructs the robotdevice 13. This coater unit 14 is operative for painting the vehiclebody 2 and built as a rotary atomizing head type coating apparatus witha rotary atomizing head 22, which will be described hereinafter. Asshown in FIG. 3, the coater unit 14 is largely constituted by a commonbody 15 and an atomizing head 19 and the like, which will be describedhereinafter.

Indicated at 15 is a common body which is fixedly mounted on the robotdevice 13, and on which a washed atomizing head 19 and a replenishedpaint cartridge 24 are to be mounted as replacements for a usedatomizing head 19′ and a used paint cartridge 24′, respectively. Asshown in FIGS. 3 and 4, the common body 15 is composed of a neck portion15A which is attached to the wrist 13D at the fore distal end of thehorizontal arm 13C and a cylindrical mount portion 15B which isintegrally formed at the fore distal end of the neck portion 15A.

Further, as shown in FIG. 5, provided on the front side of the mountportion 15B is an atomizing head coupler 15C to which an atomizing head19 is replaceably connected as described hereinafter. On the other hand,provided on the rear side of the mount portion 15B is a cartridge holdersocket 15D which replaceably hold a paint cartridge 24. Further, a feedtube receptacle hole 15E is formed axially at the center of the mountportion 15B to receive a feed tube 27 of a paint cartridge 24 therein.

In this instance, as shown in FIGS. 3, 17 and 18 and the like, the mountportion 15B of the common body 15 is formed with a pair of grip surfaces15F. These grip surfaces 15F serve as positioning portions for bringingthe mount portion 15B to position in a rotational direction and also ina vertical direction at the time when the mount portion 15B is grippedon a common body gripper 33, which will be described hereinafter. Moreparticularly, the grip surfaces 15F are in the form of indented surfaceswhich are formed in radially opposite positions on the circumference ofthe mount portion 15B. And, the grip surfaces 15F are defined by flatsurfaces 15F1 which are parallel with each other in a radial direction,and one and the other inclined surfaces 15F2 and 15F3 rising from rearand front ends of the flat surfaces 15F1, respectively. In thisinstance, one and the other inclined surfaces 15F2 and 15F3 are inclinedin axially forward and rearward directions of the mount portion 15B in adiverging fashion.

As shown in FIG. 19, each grip surfaces 15F is gripped by a radialpositioners 33D of a common body gripper 33, which will be describedhereinafter, with the flat surfaces 15F1 in abutting engagement withflat surfaces 33D1, to bring the common body 15 to position in therotational direction relative to a vertical center axis O1-O1 of achanging position “O”. Further, when the grip surfaces 15F are grippedin the radial positioner 33D of the common body gripper 33, one and theother inclined surfaces 15F2 and 15F3 are respectively abutted againstinclined surfaces 33D2 and 33D3 on the part of the radial positioner 33Das shown in FIG. 20 to locate the common body 15 in position in thevertical direction.

Denoted at 16 is a high voltage generator which is provided on the neckportion 15A of the common body 15. For example, this high voltagegenerator 16 is constituted by a Cockcroft circuit, and adapted to applya high voltage, e.g., a high voltage elevated to −60 to −120 kV, to arotary atomizing head 22 through a rotational shaft 21B of an air motor21, which will be described hereinafter.

Designated at 17 is an extruder liquid passage which is provided on theside of the common body 15 to circulate a liquid for extruding paint outof a paint cartridge 24 which is loaded on the common body side.Indicated at 18 is an extruder liquid valve which is provided in thecourse of the extruder liquid passage 17 in the common body 15. Thesupply of an extruder liquid to the paint cartridge 24 is controlled byopening and closing the extruder liquid passage 17 by this extruderliquid valve 18.

Indicated at 19 is an atomizing head which is removably connected to theatomizing head coupler 15C of the common body 15 (see FIG. 4). By thisatomizing head 19, paint which is supplied from a paint cartridge 24,which will be described hereinafter, is sprayed toward the vehicle body2. For example, two atomizing heads 19 are provided and interchangeablyused properly. As shown in FIG. 6, each atomizing head 19 is constructedas a rotary atomizing head which is constituted by a body 20, an airmotor 21, a rotary atomizing head 22 and a shaping air ring 23, whichwill be described hereinafter.

In this instance, in the description of operational actions which willbe described hereinafter, a clean atomizing head from which paint hasbeen washed of f is referred to as “a washed atomizing head 19”, and anatomizing head which is smudged with paint as a result of a coatingoperation is referred to as “a used atomizing head 19′”.

Indicated at 20 is a body of the atomizing head 19, which forms an outershell of the atomizing head 19. The body 20 is formed in a taperedcylindrical shape having a diameter which is gradually reduced in aforward direction. A motor receptacle cavity 20A is provided internallyof the body 20. On the outer peripheral side of the body 20 is providedwith, for example, three grip holes 20B (only two of which are shown inthe drawings) to be engaged with protrusive 35E which are provided on agripping member 35C of an atomizing head gripper 35 as shown in FIGS. 21and 22. Further, a positioning pin 20C is projected from the rear end ofthe body 20 to be engaged with a positioning hole (not shown) on thepart of the common body 15 for setting position in the rotationaldirection.

Denoted at 21 is an air motor which is accommodated in the motorreceptacle cavity 20A within the body 20. By an air turbine 21C of thisair motor 21, a hollow rotational shaft 21B which is rotatably supportedin a motor case 21A is driven to rotate at a high speed, for example, ata speed in the range of from 3000 r.p.m. to 150,000 r.p.m.

Indicated at 22 is a rotary atomizing head which is mounted on a foreend portion of the rotational shaft 21B of the air motor 21. This rotaryatomizing head 22 is put in high speed rotation by the air motor 21, sothat paint which is discharged from a feed tube 27 of a paint cartridge24 is sprayed in the form of finely divided particles under theinfluence of centrifugal force.

Indicated at 23 is a shaping air ring which is provided at the fore endof the body 20, on the outer peripheral side of the rotary atomizinghead 22. From this shaping air ring 23, shaping air is spurted forwardto control a spray pattern of paint particles which are sprayed from therotary atomizing head 22.

Indicated at 24 is a paint cartridge which is detachably fitted in thecartridge holder socket 15D of the common body 15. A plural number ofpaint cartridges 24 of each different colors are mounted on a mount deck42 of a cartridge changer 41 which will be described hereinafter. Asshown in FIGS. 4 and 7, each paint cartridge 24 is largely constitutedby a tank 25, a piston 26 and a feed tube 27.

In the description of operational actions which will be givenhereinafter, a paint cartridge 24 which has been replenished with paintof a next color within the tank 25 is referred to as “a replenishedpaint cartridge 24”, while an empty paint cartridge which has beenconsumed paint of a previous color within the tank 25 is referred to as“a used paint cartridge 24′”.

Indicated at 25 is a tank of the paint cartridge 24, which is in theform of a tubular container closed at opposite axial ends. Further,projected on the rear side of the tank 25 is a grip portion 25A to beclasped by cartridge grippers 48B and 48C on a swing arm 48 which willbe described hereinafter. A piston 26 is fitted in the tank 25displaceably in the axial direction, defining a paint chamber 25B and anextruder liquid chamber 25C on the front and rear sides thereof. A paintpassage 25D is provided in a front side portion of the tank 25,communicating a paint supply passage 27A of a feed tube 27 with thepaint chamber 25B.

Denoted at 27 is a feed tube which is provided at the front end of thetank 25. At a base end, the feed tube 27 is securely fixed to a frontportion of the tank 25. On the other hand, as shown in FIG. 4, in a foreend portion, the feed tube 27 is extended through the feed tubereceptacle holes 15E of the common body 15 and opened toward the rotaryatomizing head 22. Further, as shown in FIG. 7, a paint supply passage27A is formed internally of the feed tube 27 in communication with thepaint chamber 25B of the tank 25. Furthermore, the paint supply passage27A is reduced stepwise in diameter in a fore end portion of the feedtube 27 to provide a valve seat 27B.

Indicated at 28 is an extruder liquid passage on the side of the paintcartridge, which is formed in the tank 25 in communication with theextruder liquid chamber 25C. As shown in FIG. 4, this extruder liquidpassage 28 is communicated with the extruder liquid passage 17 on theside of the common body when the paint cartridge 24 is fittingly set inthe cartridge holder socket 15D on the common body 15.

Designated at 29 is a paint valve which is provided in a front endportion of the tank 25 for the purpose of on-off control of paint supplyto the atomizing head 19 from the feed tube 27. This paint valve 29 isconstituted by an axially displaceable piston 29A, and a valve body 29Bwhich is extended through the paint supply passage 27A of the feed tube27 from the piston 29A and seated on and off the valve seat 27B at itsfore end.

Now, with reference to FIGS. 2, 8 to 39, the description is directed tothe construction of an atomizing head changing and washing device 31which plays the roles of interchangeably mounting a couple of atomizingheads 19 and 19′ on the common body 15 of the coater unit 14 located onthe robot device 13 and washing a dismantled used atomizing head 19′.

Namely, indicated at 31 is an atomizing head changing and washing deviceadopted in the present embodiment. As shown in FIG. 2, the atomizinghead changing and washing device 31 is located within an operating rangeof the robot device 13 and in a position free of possibilities ofinterference with coating operations, for example, in a narrow spacebetween the tracking rail 12 and a wall of a coating booth (not shown).By this atomizing head changing and washing device 31, a used atomizinghead 19′ on the common body 15 of the coater unit 14 is replaced with awashed atomizing head 19, and the dismantled used atomizing head 19′ iswashed clean. To serve for these purposes, as shown in FIGS. 11 to 13,the atomizing head changing and washing device 31 is constituted by afixed plate 32, a common body gripper 33, an elevator 34, an atomizinghead gripper 35, and washers 36 and 37 and the like which will bedescribed hereinafter.

Denoted at 32 is a fixed plate serving as a fixing member, which is abase of the atomizing head changing and washing device 31. This fixedplate 32 is in the form of a plate-like structure which is extended in avertical direction. As shown in FIGS. 8 and 12, for example, the fixedplate 32 has its rear side securely fixed to the front side of a mountdeck 42 of a cartridge changer 41, which will be described hereinafter,and has its lower side abutted on a floor surface and the like.

Indicated at 33 is a common body gripper which is fixedly mounted in aposition where it can grip the common body 15 of the coater unit 14 onthe robot device 13, that is, in an upper portion of the fixed plate 32as shown in FIG. 14 and the like. By this common body gripper 33, thecommon body 15 is fixedly positioned in the changing position “O” of theatomizing head changing and washing device 31 at the time of replacingan atomizing head 19 and a paint cartridge 24 on the common body 15 ofthe coater unit 14.

In this instance, as shown in chained line in FIGS. 11, 13, 17 and 18,the changing position “O” of the atomizing head changing and washingdevice 31 means a position at which the grip surfaces 15F of the commonbody 15 are fixedly gripped by radial positioners 33D of the respectivegripping pawls 33C of a common body gripper 33, which will be describedhereinafter. Since the common body gripper 33 is fixedly mounted on thefixed plate 32, the changing position “O” can be determined as animmovable specific position (a specific space) which is surrounded by apair of pawls 33C. Therefore, when gripped by the common body gripper33, the common body 15 is fixedly retained in a specific position on avertical center line O1-O1 passing through the center of the changingposition “O”.

As shown in FIG. 13, the common body gripper 33 is largely constitutedby a mount frame 33A which is mounted on and forwardly projected from anupper portion of the fixed plate 32, an actuator 33B which istransversely attached to a fore distal end of the mount frame 33A, apair of gripping pawls 33C which are mounted in transversely confrontingpositions to each other on the actuator 33B for movement toward and awayfrom each other, and radial positioners 33D which are attached inconfronting positions on the gripping pawls 33C. In this instance, theactuator 33B, for example, provides drive members which are moved towardand away from each other by an air cylinder or a motor (none of whichare shown in the drawings) or the like and the gripping pawls 33C areattached to drive members to put the gripping pawls 33C in gripping andreleasing motions.

Further, as shown in FIGS. 19 and 20, after transfer to the changingposition “O” of the atomizing head changing and washing device 31 by therobot device 13, the mount portion 15B of the common body 15 of thecoater unit 14 is fixedly gripped between the gripping pawls 33C. Eachone of the gripping pawls 33C is provided with inclined surfaces 33C1 inbase and fore end portions in parallel relation with the vertical centerline O1-O1 passing through the changing position “O”. Under guidance ofthese inclined surfaces 33C1, the mount portion 15B of the common body15 is brought into alignment with the changing position “O” of theatomizing head changing and washing device 31 when gripped by thegripping pawls 33C.

The radial positioners 33D are each provided with flat surfaces 33D1which are disposed parallel with the center line O1-O1 and faced towardeach other across the center line O1-O1, and one and the other inclinedsurfaces 33D2 and 33D3 which are provided at the opposite ends of eachone of the flat surfaces 33D1. In this instance, one inclined surface33D2 is inclined substantially at the same angle as one inclined surface15F2 of the grip surface 15F on the common body 15, while the otherinclined surface 33D3 is inclined substantially at the same angle as theother inclined surface 15F3 of the grip surface 15F.

Thus, as the mount portion 15B of the common body 15 is gripped betweenthe gripping pawls 33C, the radial positioners 33D are abutted againstthe grip surfaces 15F on the mount portion 15B, and as a result thecommon body 15 is automatically set in the changing position “O”.Namely, as shown in FIG. 19, the flat surfaces 33D1 of the radialpositioners 33D are brought into abutting engagement with the flatsurfaces 15F1 of the grip surfaces 15F provided on the common body 15thereby bringing the common body 15 automatically into position in therotational direction. In addition, as shown in FIG. 20, by abuttingengagement of the inclined surfaces 33D2 and 33D3 with the inclinedsurfaces 15F2 and 15F3 of the grip surfaces 15F, the common body 15 isat the same time automatically set in position in a vertical direction.

In this instance, at the time of gripping the mount portion 15B of thecommon body 15 by the respective gripping pawls 33C and radialpositioners 33D of the common body gripper 33, a control mode isswitched to a reduced power mode as shown in Step 4 in the flow chart ofFIG. 44. Namely, the robot device 13 is switched to a reduced powermode, lowering the level of a driving force, such as a rotational torquewhich is applied to the arms 13B and 13C and the wrist 13D of the robotdevice 13 from a rotational motor or a reciprocating actuator (none ofwhich is shown in the drawings), permitting to move the arms 13B and 13Cand the wrist 13D freely by an external force. As a result, the commonbody 15 of the coater unit 14 is put, so to say, in a free state and canbe turned to an arbitrary direction by application of an external force.

Therefore, by gripping the mount portion 15B of the common body 15 whichwas delivered by the robot device 13 by use of each gripping pawls 33C,the common body gripper 33 which is mounted on the fixed plate 32 caneasily correct a positional deviation against the robot device 13 byeach inclined surface 33C1 and set the position of the mount portion 15Bof the common body 15 to the changing position “O” of the atomizing headchanging and washing device 31.

Besides, even if the common body 15 is located in a deviated position ina rotational direction as shown in FIG. 17, such a positional deviationin a rotational direction of the common body 15 can be corrected by thecommon body gripper 33 as shown in FIG. 19 by abutting engagement of theflat surfaces 33D1 of the radial positioners 33D of the common bodygripper 33 with the flat surfaces 15F1 in the grip surfaces 15F on themount portion 15B.

Further, when the grip surfaces 15F of the common body 15 are grippedbetween the radial positioners 33D, the inclined surfaces 33D2 and 33D3of the radial positioners 33D are brought into abutting engagement withthe inclined surfaces 15F2 and 15F3 on the part of the grip surfaces15F. As a consequence, even if the common body 15 is in a verticallydeviated position as shown in FIG. 18, such a vertical positionaldeviation of the common body 15 can be corrected by the common bodygripper 33 as shown in FIG. 20.

Thus, by the common body gripper 33, the coater unit 14 can beautomatically set in the proper changing position “O” of the atomizinghead changing and washing device 31 in a correctly oriented state,permitting to mount and dismantle the atomizing head 19 and paintcartridge 24 against the common body 15 free of interferences whichwould result in exertion of unduly large loads.

Indicated at 34 is an elevator which is provided on the front side ofthe fixed plate 32 to move up and down an atomizing head gripper 35 aswell as washers 36 and 37, which will be described hereinafter. Further,as shown in FIGS. 11 to 16, the elevator 34 is largely constituted by amount plate 34A which is disposed face to face with the fixed plate 32,a guide rail 34B which is located between the mount plate 34A and thefixed plate 32 to guide upward and downward movements of the mount plate34A, a feed screw 34C for moving the mount plate 34A up and down, and amotor 34D which is mounted above the fixed plate 32 to drive the feedscrew 34C.

As the feed screw 34C is rotationally driven by the motor 34D of theelevator 34, the atomizing head gripper 35, and washers 36 and 37 aremoved up and down along with the mount plate 34A to and from threevertically shifted positions (i.e., position A, position B and positionC) which will be described hereinafter.

Indicated at 35 is an atomizing head gripper which is mounted on themount plate 34A of the elevator 34. This atomizing head gripper 35 islargely constituted by a cylinder 35A which is mounted transversely on alower portion of the mount plate 34A, a movable plate 35B ofsubstantially T-shape which is attached to the cylinder 35A formovements in rightward and leftward directions, a U-shaped grippingmember 35C which is projected forward from a left side of the movableplate 35B, and other U-shaped gripping member 35D which is projectedforward from right side of the movable plate 35B. In this instance, thecylinder 35A, for example, employs a rodless cylinder type actuatoroperated by pneumatic pressure or magnetic force.

As shown in FIG. 21, each one of the left and right gripping members 35Cand 35D is provided with protrusive prongs 35E in three positions, i.e.,in right, left and inner side positions. As shown in FIG. 22, as soon asan atomizing head 19 is located in the gripping member 35C or 35D, eachprotrusive prong 35E is driven to protrude toward the atomizing head 19by supply of driving air. At this time, the respective protrusive prongs35E are urged to fit in grip holes 20B which are formed on the body 20of the atomizing head 19 and to fix the atomizing head 19 in place.

Further, as shown in FIG. 13, the atomizing head gripper 35 is soarranged that a center line P1-P1 of the gripping member 35C on the leftside is at a distance W1 from a center line P2-P2 of the gripping member35D on the right side. This interval W1 between the paired grippingmembers 35C and 35D is ½ of an interval W2 between washers 36 and 37which will be described hereinafter (W1=W2/2).

As shown in FIG. 30, when the common body 15 of the coater unit 14 isgripped by the common body gripper 33, the atomizing head gripper 35 islocated in the uppermost position A by the elevator 34. In this positionA, as shown in FIG. 31, the atomizing head gripper 35 can grip a usedatomizing head 19′ by the gripping member 35C(35D) simultaneously withthe gripping operation by the common body gripper 33.

Further, when the atomizing head gripper 35 is lowered to position B asshown in FIG. 34, the atomizing head 19′ can be dismantled from thecommon body 15. In position B, by means of the cylinder 35A, theatomizing head 19 on the gripping member 35C(35D) can be moved in aleftward direction along with the movable plate 35B as shown in FIG. 35.

In this instance, when the movable plate 35B is shifted in a rightwarddirection by the cylinder 35A, as shown in FIG. 34, the center lineP1-P1 of the gripping member 35C on the left side is located on thecenter line O1-O1 passing through the changing position “O” of thecommon body gripper 33, while the center line P2-P2 of the grippingmember 35D on the right side is located on a center line Q2-Q2 of awasher 37 on the right side. On the other hand, as shown in FIG. 35,when the movable plate 35B of the atomizing head gripper 35 is shiftedin a leftward direction by the cylinder 35A, the center line P1-P1 ofthe gripping member 35C on the left side is located on a center lineQ1-Q1 of a washer 36 on the left side, which will be describedhereinafter, while the center line P2-P2 of the gripping member 35D onthe right side is located on the center line O1-O1 passing through thechanging position “P” of the common body gripper 33.

Further, as shown in FIG. 42, by lowering the atomizing head gripper 35largely to position C, a used atomizing head 19′ which is embraced inthe gripping member 35C(35D) can be put in a waste liquid collectingcontainer 38, which will be described hereinafter.

Indicated at 36 is a left washer which is mounted on a left position onthe mount plate 34A of the elevator 34. The washer 36 is movable betweenupper and lower positions (between position D and position E) which willbe described hereinafter. As shown in FIGS. 23 and 24, the washer 36 islargely constituted by a cylinder 36A vertically mounted on a left sideportion of the mount plate 34A, a movable plate 36B substantially in theshape of a rectangular strip attached to the cylinder 36A for verticalmovements, and a washing tool 36C located in a projected position on thefront side of the movable plate 36B. In this instance, as the cylinder36A, the washer 36 employs a rodless cylinder type actuator operated bypneumatic pressure or magnetic force.

Further, the washing tool 36C is provided with a wash liquid feed tube36D for spurting a wash liquid toward the rotary atomizing head 22. Inaddition to a wash valve which opens and closes a passage in the washliquid feed tube 36D, the washing tool 36C is further provided with adriving air passage for supply of compressed air or to drive the airmotor 21, and a shaping air passage for supply of shaping air (both notshown in the drawings). The washing tool 36C as well as the wash liquidfeed tube 36D is located on the center line Q1-Q1.

On the other hand, indicated at 37 is a right side washer which islocated in a right side position on the mount plate 34A of the elevator34. This washer 37 is also movable between upper and lower positions(between position D and position E). In the same way as the washer 36 onthe left side, the washer 37 on the right side is largely constituted bya cylinder 37A, a movable plate 37B, a washing tool 37C and a washliquid feed tube 37D. The washing tool 37C as well as the wash liquidfeed tube 37D is located on the center line Q2-Q2. Therefore, as shownin FIG. 13, the left washer 36 is at a distance W2 from the right washer37.

As described above, the washing tools 36C and 37C of the washers 36 and37 are movable to and from an upper lifted position D on the mount plate34A (e.g., the position shown in FIG. 31) and a lowered position E inthe proximity of the waste liquid collecting container 38 (e.g., theposition shown in FIG. 42 by the cylinders 36A and 37A).

The washing tools 36C and 37C are in a standby state when in the upperlifted position D. When in the lowered position E, the wash liquid feedtube 36D or 37D of the washing tool 36C or 37C is inserted into a usedatomizing head 19′ to take a washing position. In this washing position,a wash liquid is spurted out from the washing liquid feed tube 36D or37D to wash off paint which has deposited on the used atomizing head19′.

Indicated at 38 are left and right waste liquid collecting containerswhich are located underneath the left and right washers 36 and 37,respectively. Each one of these waste liquid collecting container 38 isconstituted by a bottomed cylindrical container which is located in avertically aligned position relative to the washing tool 36C or 37C.Further, each one of the waste liquid collecting containers 38 serves tocollect a waste wash liquid which is scattered around while an atomizinghead 19 is washed by the washer 36 or 37. Each waste liquid collectingcontainer 38 is internally provided with nozzles (not shown in thedrawings) to spurt a wash liquid toward outer peripheral surface of therotary atomizing head 22 and shaping air ring 23 and the like to washoff paint which has deposited on outer peripheral surfaces of the rotaryatomizing head 22 and shaping air ring 23.

Now, following is a description of the construction of a cartridgechanger 41 which is capable of interchangeably mounting a selected paintcartridge 24 on the common body 15 of the coater unit 14 which isprovided on the robot device 13, with reference to FIGS. 8 to 10 and 25to 29.

Namely, indicated at 41 is a cartridge changer which is located behindthe atomizing head changing and washing device 31. This cartridgechanger 41 serves to replace a used paint cartridge 24′ on the commonbody 15 of the coater unit 14 by a fresh paint cartridge 24 which hasbeen replenished with paint. As shown in FIGS. 25 and 26, the cartridgechanger 41 is largely constituted by a mount deck 42, a paintreplenishing unit 43 and a cartridge transfer mechanism 44, as describedbelow.

Denoted at 42 is a mount deck which constitutes a main body structure ofthe cartridge changer 41. This mount deck 42 is adapted to hold a pluralnumber of paint cartridges side by side, and located within an operatingrange of a swing arm 48 which will be described hereinafter. In thisinstance, the mount deck 42 is constituted by a frame structure 42Abuilt in a rectangular shape which is elongated in a transversedirection (in the transfer direction of the vehicle body 2), arectangular shaped lower deck plate 42B which is supported substantiallyhorizontally on the intermediate position closer to the bottom of theframe structure 42A, and a rectangular shaped upper deck plate 42C whichis supported substantially horizontally on the intermediate positioncloser to the top of the frame structure 42A.

As shown in FIG. 10, the upper deck plate 42C is formed with atransversely extending slot 42D at a position closer to its front side.This slot 42D is provided to permit linear leftward and rightwardmovements of a cylindrical swiveling column 46B of an arcuate movingportion 46, which will be described hereinafter. Further, the mount deck42 is enclosed in a sheet-like decorative cover 42E composed by a thinplate (see FIGS. 1 and 2).

Indicated at 43 are a plural number of paint replenishing units (seeFIGS. 25 and 26) which are mounted on the lower deck plate 42B of themount deck 42. By one of these paint replenishing units 43, a used paintcartridge 24′ is replenished with paint of a color same as a previousone. A suitable number of paint replenishing units 43 are provideddepending upon the number of paint colors or types to be replenished.Furthermore, each one of the paint replenishing units 43 is connected toa paint source (which is not shown). A used paint cartridge 24′ is setat the paint replenishing units 43 to insert a feed tube 27 from theupper side. In such a case, the paint chamber 25B of the tank 25 will bereplenished through the paint supply passage 27A of the feed tube 27.

In this instance, as indicated by broken lines in FIG. 26, the pluralnumber of paint replenishing units 43, for example, four units arelocated on the loci of arcuate line S drown by radius R about a pivotingpoint Sp of a swing arm 48 moved by arcuate moving portion 46.Furthermore, the paint replenishing units 43 are arranged in six arcuaterows S1 to S6 from left side to the right, for example, at uniformintervals in the longitudinal direction of the mount deck 42, each rowhaving four replenishing units 43 located along an arcuate lines acrossthe width (between the front and rear sides) of the mount deck 42.

In such a case, the paint cartridges 24 which is provided at the paintreplenishing unit 43 to supply paint are arrayed in six arcuate rows atuniform intervals as four paint cartridges in each row which are locatedon the arcuate line S, similar to the respective paint replenishing unit43.

Further, as shown in FIG. 26, of the six arcuate rows S1 to S6 of whichthe paint replenishers 43 (the paint cartridge 24), for example, thearcuate row S3 which is in the third position from left is located in anintersecting position relative to the vertical center line O1-O1 passingthrough the head changing position “O” of the atomizing head changingand washing device 31. Namely, the arcuate row S3 is located on a locusof a movement taken at the time of transferring a replenished paintcartridge 24 on the mount deck 42 to replace a used paint cartridge 24′on the common body 15 which is fixedly gripped at the changing position“O” of the atomizing head changing and washing device 31.

Indicated at 44 is a cartridge transfer mechanism which is provided onthe mount deck 42. This cartridge transfer mechanism 44 is a mechanismfor transferring a used paint cartridge 24′ or a replenished paintcartridge 24 along an arcuate transfer line to or from a paintreplenishing unit 43 on the mount deck 42 and the common body 15 of thecoater unit 14 located in the changing position “O”. The cartridgetransfer mechanism 44 is constituted by a linear moving portion 45, anarcuate moving portion 46, a vertical moving portion 47 and a swing arm48, which are described below.

Indicated at 45 is a linear moving portion which is provided on theupper deck plate 42C of the mount deck 42. This linear moving portion 45is operative to shift positions of an arcuate moving portion 46, avertical moving portion 47 and a swing arm 48, which will be describedhereinafter, linearly in the longitudinal direction of the mount deck42. In this instance, as shown in FIGS. 10 and 25, the linear movingportion 45 is largely constituted by a pair of guide rails 45A which arelocated longitudinally on the opposite sides of the slot 42D in theupper deck plate 42C, a carriage 45B which is movably mounted on theguide rails 45A, a screw feeder 45C which is located between the guiderail 45A and the slot 42D, and a motor 45D which is mounted on a rightend portion of the upper deck plate 42C to drive the screw feeder 45C.As shown in FIG. 27, the screw feeder 45C is constituted by a screw rod45C1, and a block 45C2 which is attached to the lower side of thecarriage 45B, in threaded engagement with the screw rod 45C1.

Indicated at 46 is an arcuate moving portion which is mounted on thecarriage 45B of the linear moving portion 45, the arcuate moving portion46 turn (swing) a cartridge gripper 48B provided at the fore end alongan arcuate path, by oscillating (revolving) a swing arm 48 which will bedescribed hereinafter, in horizontal plane upon pivoting point Sp.Further, as shown in FIG. 27, the arcuate moving portion 46 is largelyconstituted by a stationary cylindrical outer shell 46A which is fixedlyprovided substantially at the center of the carriage 45B, a swivelingcolumn 46B rotatably fitted in the outer shell 46A for swivelingmovements about a vertical axis, and a rotational drive motor 46C forturning the swiveling column 46B which is mounted on the carriage 45B.

In this instance, the swiveling column 46B is rotatably supported in theouter shell 46A through a bearing 46B1. A gear 46B2 is provided on theouter periphery of an upper end portion of the swiveling column 46B, inmeshing engagement with a gear 46C1 on the part of the rotational drivemotor 46C. As the rotational drive motor 46C is rotatably actuated, theswiveling column 46B is turned through the gears 46C1 and 46B2. Thus,the swing arm 48 can be turned (can be put in a swinging motion) by thearcuate moving portion 46 which is very simple in construction.

Designated at 47 is a vertical moving portion which is attached to theswiveling column 46B of the arcuate moving portion 46. This verticalmoving portion 47 is provided for lifting a swing arm 48 up and down(upward or downward shifts of arm position), which will be describedhereinafter. Namely, as shown in FIGS. 27 and 28, the vertical movingportion 47 is largely constituted by a guide member 47A which issecurely fixed to the inner periphery of the swiveling column 46B of thearcuate moving portion 46 and extended downward of the swiveling column46B, a lifter block 47B which is vertically and movably mounted on theguide member 47A, a rod screw 47C which is extended vertically androtatably within the guide member 47A and meshed with a threaded meshingmember 47B1 of the lifter block 47B, and a motor 47D which is mounted onthe carriage 45B of the linear moving portion 45 for rotationallydriving the rod screw 47C. Further, an arm body proper 48A of a swingarm 48 is securely attached to the lifter block 47B.

Indicated at 48 is a swing arm which is attached to the lifter block 47Bof the vertical moving portion 47. This swing arm 48 is operative topick up paint cartridges 24 which are arrayed on the upper deck plate42C of the mount deck 42. As shown in FIGS. 28 and 29, the swing arm 48is largely constituted by an arm body proper 48A which is horizontallyextended from the lifter block 47B, and left and right cartridgegrippers 48B and 48C which are provided side by side at a fore distalend of the arm body proper 48A.

The cartridge gripper 48B on the left side is provided with a pair ofgripping pawls 48B1 which are turned toward and away from each other bymeans of an actuator (not shown). These gripping pawls 48B1 are turnedtoward each other at the time of catching a grip knob 25A which isprovided on the tank 25 of a paint cartridge 24. Similarly, thecartridge gripper 48C on the right side is provided with paired grippingpawls 48C1 which can be likewise turned toward and away from each otherby means of an actuator (not shown). In this instance, each one of thecartridge grippers 48B and 48C is located on an arc of radius R aroundthe pivoting point Sp of the arcuate moving portion 46.

In this instance, the swing arm 48 of the cartridge transfer mechanism44 is linearly moved in a longitudinal direction (in a leftward orrightward direction of the mount deck 42) by the linear moving portion45, and put in a swing motion (an arcuate movement) by the arcuatemoving portion 46 simultaneously with a lift up or a lift down movement(an upward or downward movement) by the vertical moving portion 47.Thus, the cartridge transfer mechanism 44 can pick up a replenishedpaint cartridge 24 from a replenishing unit 43 and transfer the same toa position on the vertical center line O1-O1 passing through thechanging position “O” of the atomizing head changing and washing device31. Also, the cartridge transfer mechanism 44 can return a used paintcartridge 24′ to the paint replenishing unit 43.

At this time, the cartridge gripper 48B of the swing arm 48 is lifted upto position F (shown in FIGS. 31 and 39), and lowered from position F toposition G (shown in FIGS. 34 and 37), at the time of replacing a usedpaint cartridge 24′ with a replenished paint cartridge 24 by an arcuatemoving portion 46. On the other hand, for replacing a used paintcartridge 24′ by a replenished paint cartridge 24, the cartridge gripper48B can be stopped at the level of position H (shown in FIGS. 35 and 36)which is lower than position F, because there is no paint cartridge 24′which is in the way as an obstacle.

The above-described paint coating system 11 of the present embodiment isput in operation in the manner as follows.

In the first place, in order to paint a vehicle body 2 which is beingtransferred by the conveyer 3, the robot device 13 is moved on and alongthe tracking rail 12 while coating operation is put in action by therobot device 13. At this time, a washed clean atomizing head 19 isconnected to the head coupler portion 15C of a common body 15, and areplenished paint cartridge 24 which is filled with a desired paintcolor is set in the cartridge holder portion 15D. Thus, a cartridge typerotary atomizing head type coater unit 14 is set up by the common body15, atomizing head 19 and the paint cartridge 24.

In order to start a coating operation by the use of the coater unit 14,the robot device 13 is put in action to face the rotary atomizing head22 of the atomizing head 19 toward the vehicle body 2. The rotaryatomizing head 22 is put in high speed rotation by the air motor 21,while shaping air is spurted out from the shaping air ring 23. Further,a high voltage is applied to the rotary atomizing head 22 from the highvoltage generator 16 through the air motor 21. In this state, theextruder liquid valve 18 and the paint valve 29 are opened, whereuponthe paint in the tank 25 of the paint cartridge 24 is pushed out towardthe rotary atomizing head 22 from the feed tube 27 by the action of theextruder liquid. As a consequence, paint particles which are chargedwith a high voltage are sprayed toward the vehicle body 2 by the rotaryatomizing head 22.

Upon finishing a paint coating operation on the vehicle body 2, a usedatomizing head 19′ and a used paint cartridge 24′ are replaced by awashed atomizing head 19 and a replenished paint cartridge 24.

Given below is a more detailed description of operations for replacementof the atomizing head 19 and the paint cartridge 24, with reference tothe flow chart of FIG. 44 and to the schematic illustration explanatoryof FIGS. 30 to 43.

As described above, upon finishing a coating operation on a vehicle body2 by the coater unit 14 (Step 1), the robot device 13 is put in anaction to bring the coater unit 14 to the changing position “O” of theatomizing head changing and washing device 31 as indicated in two dotline in FIG. 30 (Step 2). At this changing position “O”, the common body15 of the coater unit 14 is located between each gripping pawls 33C atthe common body gripper 33 of the atomizing head changing and washingdevice 31 as shown in two dot line in the figure. On the other hand, aused atomizing head 19′ is located in a position within a reach of theleft side of the gripping member 35C of the gripping members 35C, 35D ofthe atomizing head gripper 35 which is shown in FIG. 30.

In Step 3, a judgment is made as to whether or not the coater unit 14has already reached the changing position “O” of the atomizing headchanging and washing device 31. The control proceeds to Step 4 in casethe coater unit 14 is found to have already been located in the changingposition “O” of the atomizing head changing and washing device 31 asshown in two dot line in FIG. 30.

In Step 4, the robot device 13 is switched to a reduced power mode. Inthis case of the paint coating system 11, the coater unit 14 whichshould be located correctly at the changing position “O” might have beenlocated in a deviated position for some reason. Therefore, in Step 4,the robot device 13 is put in a reduced power mode, lowering the levelsof driving forces of rotating motors and reciprocating actuators (bothnot shown) which arcuate the arms 13B and 13C and the wrist 13D of therobot device 13. That is, in Step 4, the robot device 13 is controlledto make the common body 15 freely movable by application of an externalforce to the coating unit 14. Thus, the coater unit 14 is put in afreely movable state.

In Step 5, as shown in FIG. 31, as soon as the coater unit 14 isdelivered to the changing position “O” of the atomizing head changingand washing device 31 by the robot device 13, the mount portion 15B onthe common body 15 of the coater unit 14 is gripped between the rightand left gripping pawls 33C of the common body gripper 33. The coaterunit 14 is put in a free state in Step 4 before gripping the common body15 of the coater unit 14 by the right and left gripping pawls 33C of thecommon body gripper 33. Therefore, as the mount portion 15B of thecommon body 15 is gripped between the gripping pawls 33C, a positionaldeviation between the robot device 13 can be corrected automatically bythe inclined surfaces 33C1 to set the mount portion 15B of the commonbody 15 exactly at the predetermined specific changing position “O” ofthe atomizing head changing and washing device 31.

In case the common body 15 is deviated in a rotational direction, suchpositional deviation in a rotational direction can also be automaticallycorrected as the flat surfaces 15F1 of the grip surfaces 15F provided atthe mount portion 15B are gripped between the flat surfaces 33D1 of theradial positioners 33D. Accordingly, as shown in FIG. 31, by the commonbody gripper 33, the common body 15 can be fixed in a predeterminedspecific changing position “O” on the center line O1-O1 in between thegripping paws 33C, in a correctly oriented state in a radial directionand exactly at a predetermined height.

In this instance, Step 4 for switching the coater unit 14 provided atthe robot device 13 to a freely movable state and Step 5 for grippingthe common body 15 of the coater unit 14 are executed substantially atthe same time. If necessary, the order of Step 4 and Step 5 may bereversed, putting the common body 15 on the robot device 13 in a freestate after the common body 15 of the coater unit 14 is gripped.

While Step 4 and Step 5 are being executed, the cartridge changer 41 isput in operation. Namely, before the common body 15 is gripped by thecommon body gripper 33 in Step 5, the cartridge changer 41 is put inoperation for preparing a replenished paint cartridge 24 to be used in anext coating operation. As shown in FIG. 32, for example, this cartridgechanger 41 catches a left rear positioned replenished paint cartridge 24on the arcuate row S1 of plural number of replenished paint cartridgesby the right cartridge gripper 48C of the swing arm 48. In this state,the vertical moving portion 47 disconnect the replenished paintcartridge 24 from a paint replenishing unit 43 by lifting up the swingarm 48 along with the replenished paint cartridge 24.

In the next place, by the linear moving portion 45 of the cartridgechanger 41, the position of the swing arm 48 is shifted in a rightwarddirection from the position of FIG. 32 to the position of FIG. 33,locating its cartridge gripper 48B on the arcuate row S3 coinciding witha locus of a transfer movement. In this state, by the arcuate movingportion 46, the swing arm 48 is swung forward, locating the leftcartridge gripper 48B without the paint cartridge 24, on the center lineO1-O1 and above the changing position 101 as shown in FIGS. 31 and 33.At this time, the vertical moving portion 47 lift the feed tube 27 ofthe replenished paint cartridge 24 to the higher position F, preventingnot to contact with other obstacles. Although a linear movement of theswing arm 48 by the linear moving portion 45 is described separatelyfrom an arcuate swinging movement of the swing arm 48 by the arcuatemoving portion 46 of course, the swing arm 48 may be simultaneously putin linear and arcuate swinging movements.

Now, as shown in FIG. 31, as soon as the left cartridge gripper 48Bwithout the paint cartridge 24 is located on the center axis O1-O1 andabove the changing position “O”, the operation proceeds to Step 6. InStep 6, as shown in FIG. 34, the atomizing head gripper 35 is put in anaction of gripping a used atomizing head 19′ by the gripping member 35C,followed by an action of lowering the atomizing head gripper 35 to theposition B to dismantle the used atomizing head 19′ from the common body15. Further, in Step 7, the swing arm 48 is lowered to the position G togrip a used paint cartridge 24′ by the left cartridge gripper 48B. Then,as shown in FIG. 35, the swing arm 48 is lifted up to the position H bythe vertical moving portion 47 to draw the used paint cartridge 24′ outof the common body 15.

In this instance, Step 6 for dismantling a used atomizing head 19′ fromthe common body 15 and Step 7 for unloading a used paint cartridge 24′from the common body 15 may be reversed in order, or may be executedsimultaneously.

Now, as soon as the feed tube 27 of the paint cartridge 24′ is extractedout of the atomizing head 19′, the used atomizing head 19′ which isgripped on the gripping member 35C on the left side is moved by thecylinder 35A as far as a position on the center line Q1-Q1 of the washer36 on the left side, while the washed clean atomizing head 19 which isgripped on the gripping member 35D on the right side is shifted to aposition on the center line O1-O1 and below the changing position “O”,as shown in FIG. 35.

Now, in Step 8, as shown in FIG. 36, the gripping member 35D of theatomizing head gripper 35 is lifted up to position A to mount the washedclean atomizing head 19 which is gripped by the gripping member 35D onthe common body 15. On the other hand, the cartridge grippers 48B and48C of the swing arm 48 are moved to the left side to relocate thereplenished paint cartridge 24 gripped by the right cartridge gripper48C in a position on the center line O1-O1 and above the changingposition “O”. At this time, by the vertical moving portion 47, thecartridge grippers 48B and 48C are lifted up to position H which is at alower level than position F, shortening time which is required forshifting the position.

Now, the control goes to Step 9 as soon as the replenished paintcartridge 24 is located in a position over the changing position “O”. InStep 9, as shown in FIG. 37, the cartridge gripper 48C is lowered toposition G to load the replenished paint cartridge 24 into the commonbody 15. Thereafter, as shown in FIG. 38, the paint cartridge 24 isreleased from the cartridge gripper 48C as the latter is lifted up toposition F.

Similarly to above-described Step 6 and Step 7, if desired, Step 8 formounting a washed clean atomizing head 19 on the common body 15 and Step9 for loading a replenished paint cartridge 24 on the common body 15 maybe reversed in order or executed simultaneously.

As soon as the coater unit 14 becomes ready for a next coating operationby replacing a washed clean atomizing head 19 and a replenished paintcartridge 24 on the common body 15, the control goes to Step 10 tocancel the reduced power mode of the device force for the robot device13. In Step 10, in addition to cancellation of the reduced power mode,the gripping force of the common body gripper 33 as well as that of theatomizing head gripper 35 is canceled to release the atomizing head 19.In this state, as shown in FIG. 39, the swing arm 48 which carries theused paint cartridge 24′ is moved toward the mount deck 42 of thecartridge changer 41. At the same time, the robot device 13 which is nowcontrolled in a normal drive mode is moved to put the coater unit 14 ina coating standby position on the side of a vehicle body 2.

On the other hand, concurrently with Step 10 or after Step 10, thecartridge changer 41 is put in an operation of returning the used paintcartridge 24′, which has been dismantled from the common body 15, to aspecific position on the mount deck 42. Namely, as shown in FIG. 40, thecartridge gripper 48B which holds the used paint cartridge 24′ is movedto the rear side by the arcuate moving portion 46 along an arcuate rowS3. Thus, as shown in FIG. 4, by the action of the arcuate movingportion 46, the used paint cartridge 24′ is relocated in a specifiedposition at the upper side of the paint replenishing unit 43 on thearcuate row S3. In this state, by the vertical moving portion 47, theused paint cartridge 24′ is lowered together with the cartridge gripper48B and connected to a paint replenishing unit 43. Consequently, thepaint is replenished at this point.

In a next step, in Step 11, as shown in FIG. 42, the atomizing headgripper 35 is lowered to position C by the elevator 34 to put a fore endportion of the used atomizing head 19′ in the waste liquid collectingcontainer 38. Further, the washing tool 36C of the left washer 36 islowered to position E to insert the wash liquid tube 36D in the usedatomizing head 19′. In this state, a wash liquid is spurted out from thewash liquid tube 36D of the washer 36 to wash the rotary atomizing head22 without scattering around splashes of the wash liquid.

Upon finishing a washing operation on the atomizing head 19, as shown inFIG. 43, the atomizing head gripper 35 is elevated to position A, andthe washer 36 is elevated to position D. Accordingly, it is possible tostand by for the next operation, exchanging the atomizing head 19, 19′and the paint cartridge 24, 24′.

As described above, according to the present embodiment, the cartridgechanger 41 is constituted by the linear moving portion 45 which isadapted to shift the position of the swing arm 48 linearly in alongitudinal direction (rightward or leftward) of the mount deck 42, thearcuate moving portion 46 which put the swing arm 48 in a swingingmotion (an arcuate movement) in a horizontal plane, the vertical movingportion 47 which moves the swing arm 48 attached to the arcuate movingportion 46 upward and downward (the heave) and the swing arm 48 whichhold the paint cartridge 24 attached to the vertical moving portion 47.

Thus, by putting the swing arm 48 in an arcuate swinging motions, thearcuate moving portion 46 can move the cartridge grippers 48B and 48C ina longitudinal direction (in a leftward or rightward direction) and in atransverse direction (in a forward or rearward direction) of the mountdeck 42. Therefore, the cartridge changer 41 can be built in a morecompact form as compared with a handling robot with a multiarticular armor a cartridge changer incorporating a double layered complicate XYtable. That is to say, the paint coating system 11 can be installed evenin a space which has thus far been considered too narrow forinstallation.

In case it becomes necessary to increase the number of paint cartridges24 on the mount deck 42, this can be coped with simply by elongating theguide rail 45A of the linear moving portion 45.

On the other hand, the cartridge changer 41 has a plural number of paintcartridges 24 and the paint replenishing unit 43 arrayed in six arcuaterows S1 to S6 in longitudinal direction of the mount deck 42 of radius Raround a swing arm pivoting point Sp of the arcuate moving portion 46,four of them in each row. Of the six arcuate rows S, the third row S3 islocated on passing through the changing position “O” of the atomizinghead changing and washing device 31.

Thus, simply by putting the swing arm 48 in a swinging motion across thewidth of the mount deck 42, the cartridge changer 41 can relocate apaint cartridge 24 on the cartridge gripper 48C at the changing position“O”. This means that the cartridge changer 41 can operate veryefficiently in relocating paint cartridges 24.

Further, according to the present embodiment, the common body gripper 33is mounted on the fixed plate 32 of the atomizing head changing andwashing device 31, thereby fixedly gripping a common body 15 of a coaterunit 14 in a predetermined position at the time of replacing anatomizing head 19 and a paint cartridge 24. Therefore, a common body 15can be fixedly retained in position by the common body gripper 33 whilereplacing an atomizing head 19 and a paint cartridge 24 on the commonbody 15 of the coater unit 14. Thus, the common body gripper 33 is soarranged to locate a common body 15 in a predetermined changing position“O” of the atomizing head changing and washing device 31.

That is, according to the present embodiment, the common body gripper 33is adapted to absorb positional deviations which might occur dependingupon repeated positioning accuracy of the arms 13B and 13C of the robotdevice 13, as well as positional deviations which might have occurred inthe course of installation of the robot device 13, the atomizing headchanging and washing device 31 and the cartridge changer 41. It followsthat the coater unit 14 can be located exactly in the predeterminedimmovable changing position “O” each time when replacing the atomizinghead 19 and the paint cartridge 24.

Since a common body 15 is accurately located at a predetermined changingposition “O” of the atomizing head changing and washing device 31, anatomizing head 19 and a paint cartridge 24 can be attached to ordetached very smoothly without necessitating forcible actions. Thus, itcontributes to suppress abrasion and bruises of the common body 15,atomizing head 19 and paint cartridge 24 to guarantee higher durabilityand reliability, while permitting a reduction in maintenance cost of thecoating line 1.

Further, the accuracy in locating a common body 15 of a coater unit 14exactly at a predetermined changing position “O” of the atomizing headchanging and washing device 31 permits to carry out an installation workfor the robot device 13 in a more efficient and facilitated manner, andto fabricate and install the atomizing head changing and washing device31 and the cartridge changer 41.

Furthermore, it is possible to allow a significant reduction in cost ofthe coating line 1 as a whole.

Further, since the common body gripper 33 is mounted in a fixed state onthe fixed plate 32, the common body 15 can be gripped in the sameposition every time. That is to say, the atomizing head changing andwashing device 31 as well as the paint cartridge changer 41 can smoothlymount or dismantle an atomizing head 19 or a paint cartridge 24 on orfrom the common body 15 which is located exactly in a predeterminedposition.

On the other hand, according to the present embodiment, when the commonbody 15 is gripped by the common body gripper 33, the robot device 13 iscontrolled in a reduced power mode in which driving forces (drivingtorques) of the robot arms 13B and 13C and wrist 13D are cut down to alow level, permitting to move the common body 15 freely by applicationof an external force. Thus, the coater unit 14 which is mounted on thewrist 13D is now, so to say, in a free state and can be moved in anarbitrary direction by an external force. Accordingly, in case there isa positional deviation between the coater unit 14 and the common bodygripper 33, the coater unit 14 can be located accurately at the changingposition “O” without being affected or obstructed by the driving forceof the robot device 13.

Besides, the grip surfaces 15F are provided on the common body 15. Onthe other hand, paired gripping pawls 33C are provided on the part ofthe common body gripper 33 for gripping and locating the common body 15at the changing position “O”, in combination with the radial positioners33D which are provided on the gripping pawls 33C and brought intoabutting engagement with the grip surfaces 15F of the common body 15 togrip the common body 15 in position in a radial direction and in avertical direction as well.

Thus, by the common body gripper 33, the common body 15 of the coaterunit 14 can be automatically located in a predetermined specificchanging position “O” accurately in both vertical and radial directions.As a result, an atomizing head 19 and a paint cartridge 24 can besmoothly mounted on or dismantled from the common body 15 withoutapplying forcible connecting and disconnecting actions, to guaranteehigher reliability and elongated service life.

In the above-described embodiment, by way of example, the fixed plate 32of the atomizing head changing and washing device 31 is securely fixedto the mount deck 42 of the cartridge changer 41. However, needless tosay, the present invention is not limited to this particular exampleshown. For example, the fixed plate 32 may be provided independently andseparately of the mount deck 42 of the cartridge changer 41 as long asit is located within a reach of the cartridge grippers 48B and 48C onthe swing arm 48.

Further, in the above-described preferred embodiment, the mount deck 42of the cartridge changer 41 is arranged to hold paint cartridges 24(paint replenishing units 43) in six arcuate rows S1 to S6 of radius Rabout a shifting swing arm pivoting point Sp in the longitudinaldirection along the mount deck 42, with four paint cartridges in eachone of the arcuate rows S1 to S6. However, the present invention is notlimited to the particular example shown. The mount deck 42 may bearranged to hold two, three or more than five paint cartridges 24 ineach one of less than five or more than seven arcuate rows S which areprovided at intervals in the longitudinal direction.

Furthermore, in the above-described preferred embodiment, the mount deck42 is by way of example arranged such that the changing point “O” of theatomizing head changing and washing device 31 is located on an extensionof an arc of the third arcuate row S3 of paint cartridges 24 (paintreplenishing units 43). However, the present invention is not limited tothe particular example shown. If desired, the changing position “O” maybe located on an extension of an arc of any one of other arcuate rowsS1, S2 and S4 to S6 or on an arc which is drawn separately from the arcsof the arcuate rows S1 to S6.

Furthermore, in the above-described embodiment, the atomizing head 19 isshown as an atomizing head of the rotary atomizing head type whichprovides a rotary atomizing head 22. However, the present invention isnot limited to this particular type and can be applied to atomizingheads of other types, for example, to an atomizing head with pneumaticor hydraulic atomization nozzles.

1. A paint coating system, composed of: a robot device (13) operative totake coating actions; a coater unit (14) having a common body (15)fixedly mounted on said robot device (13) and an atomizing head (19,19′) replaceably attached to said common body (15) for spraying atomizedpaint particles; a paint cartridge (24, 24′) replaceably attached tosaid common body (15) of said coater unit (14) to supply paint to saidatomizing head (19); an atomizing head changing and washing device (31)adapted to replace a used atomizing head (19′) on said common body (15)of said coater unit (14) by a washed clean atomizing head (19) and towash a dismantled atomizing head (19′) clean; and a cartridge changer(41) adapted to pick up a selected paint cartridge (24) among a pluralnumber of replenished paint cartridges (24) arrayed on a mount deck(42), and to replace a used paint cartridge (24′) on said common body(15) of said coater unit (14) in a changing position “0” of saidatomizing head changing and washing device (31); characterized in thatsaid cartridge changer (41) comprises a swing arm (48) adapted toreplace said paint cartridge (24, 24′) while being swung to and froabout a swing arm pivoting point (Sp) along an arcuate path (S) betweena position of said replenished paint cartridge (24) on said mount deck(42) and a changing position “O” of said atomizing head changing andwashing device (31).
 2. A paint coating system as defined in claim 1,wherein said replenished paint cartridges (24) on the mount deck (42)are arranged in arcuate rows around said swing arm pivoting point (Sp).3. A paint coating system as defined in claim 1, wherein said cartridgechanger (41) is composed of said mount deck (42) adapted to mount saidreplenished paint cartridges (24) located in arcuate rows about saidswing arm pivoting point (Sp), an arcuate moving portion (46) providedon said mount deck (42) and circulated to and fro about said pivotingpoint (Sp), a vertical moving portion (47) provided on said arcuatemoving portion (46) for vertical upward and downward movements, and saidswing arm (48) which extends in a horizontal plane attached to saidvertical moving portion (47) at a base end and provided with cartridgegrippers (48B, 48C) at and on a fore free end thereof.
 4. A paintcoating system as defined in claim 1, wherein said cartridge changer(41) is composed of said mount deck (42) adapted to mount saidreplenished paint cartridges (24) located in a plural number of radiallyspaced arcuate rows (S) around said swing arm pivoting point (Sp), alinear moving portion (45) for shifting said swing arm pivoting point(Sp) provided on said mount deck (42) in a longitudinal direction, anarcuate moving portion (46) provided on said linear moving portion (45)circulated to and fro about said pivoting point (Sp), a vertical movingportion (47) provided on said arcuate moving portion (46) for verticalupward and downward movements, and said swing arm (48) which extends ina horizontal plane attached to said vertical moving portion (47), at abase end and provided with cartridge grippers (48B, 48C) at and on afore free end thereof.
 5. A paint coating system as defined in claim 1,wherein said atomizing head changing and washing device (31) is providedwith a common body gripper (33) to grip and locate said common body (15)of said coater unit (14) at said changing position “O”, and saidcartridge changer (41) is adapted to replace said paint cartridge (24,24′) while said common body (15) is gripped by said common body gripper(33).